what is this why directv install it

i only have 3 D12-700 the guy put this on the line for just 1 of the box i take it off cause it was getting hot to the touch real hot
if someone could explain for me (1) whats it's for (2) what will happen if i removed it, everything i read on google does not explain the difference if i keep it or remove it

hmmm did i mention the installer that install this try to sell me a pole for the dish under the table, he said it cost $75 but he could sell me one for $45 cause without the pole he cannot install the dish, he said the pole that came with the new dish will not work up to code i need a extended pole, i refuse so he used a existing dish that was install on the house already, he install the above device and connect it to my router but couldnt explain what it was for, i call directv and they said i wasnt supposed to be charge they send out another installer the next day he removed everything and put up a new dish cause it's a new installation
however i think he did not see this and left it cause i disconnect it